Seatbelt retractor

ABSTRACT

An automatic locking seatbelt retractor includes a rotatable reel biased in a belt retracting direction and having its end plates provided by circular peripherally toothed like ratchet members engageable by a rotatable spring biased pawl to block movement of the reel in an extending direction. A rotatable cam plate frictionally driven by the reel between two limit positions includes two spaced peripheral shoulders. Each shoulder is engageable with the pawl in alternate limit positions to hold the pawl out of engagement with the teeth of the ratchet members. A pivoted blocking lever is movable between blocking and unblocking positions with respect to the pawl. A pivoted control lever is linked to the blocking lever and biased to either of two positions by an overcenter torsion spring. A reel-driven ring gear includes peripherally spaced abutments engageable with the control lever. When the reel is in a fully belt-retracted position, the cam plate is in one limit position and the blocking lever is in blocking position. One of the cam plate abutments and the blocking lever engage the pawl to hold the pawl out of engagement with the teeth of the ratchet members. When the reel is rotated in a belt-extending direction and a predetermined length of belt is extended, the cam plate is frictionally driven to the other limit position and the other abutment of the cam plate engages the pawl. An abutment of the ring gear engages and then passes the control lever to move the control lever from one position to the other and in turn move the blocking member from blocking to unblocking position. Upon slight retraction and then extension of the belt after buckled to another belt to form a belt assembly, the cam plate is rotated toward the one limit position and the other abutment of the cam plate thereupon moves out of engagement with the pawl. The pawl is then spring biased into engagement with like teeth of the ratchet members and prevents further extension of the belt. As the belt is retracted, the cam plate is moved to the one limit position and the one plate abutment engages the pawl to hold it out of engagement with the ratchet members. The one abutment of the ring gear passes the control lever, and the other abutment of the ring gear engages the control lever immediately adjacent the fully retracted position of the belt to move the control lever to the one position and move the blocking lever to blocking position.

United States atet [72} Inventor George Edward Frost Birmingham. Mich.

[2-1] Appl. No. 1.197

(22] Filed Jan- 7, 1970.

[45] Patented Aug. 10, 1971 [73] Assignec General Motors CorporationDetroit, Mich.

[54] SEA'I'BELT RETRACTOR Primary Examiner- Stanley N. GilreathAssistant Examiner-werner H. Schroeder Anorneysw. E. Finken and HerbertFurman ABSTRACT: An automatic locking seatbelt retractor includes arotatable reel biased in a belt retracting direction and having its endplates provided by circular peripherally toothed like ratchet membersengageable by a rotatable spring biased pawl to block movement of thereel in an extending direction. A rotatable cam plate frictionallydriven by the reel between two limit positions includes two spacedperipheral shoulders. Each shoulder is engageable with the pawl inalternate limit positions to hold the pawl out of engagement with theteeth of the ratchet members. A pivoted blocking lever is movablebetween blocking and unblocking positions with respect to the pawl. Apivoted control lever is linked to the blocking lever and biased toeither of two positions by an overcenter torsion spring. A reel-drivenring gear includes peripherally spaced abutments engageable with thecontrol lever. When the reel is in a fully belt-retracted position, thecam plate is in one limit position and the blocking lever is in blockingposition. One of the cam plate abutments and the blocking lever engagethe pawl to hold the pawl out of engagement with the teeth of theratchet'members. When the reel is rotated in a belt-extending directionand a predetermined length of belt is extended, the cam plate isfrictionally driven to the other limit position and the other abutmentof the cam plate engages the pawl. An abutment of the ring gear engagesand then passes the control lever to move the control lever from oneposition to the other and in turn move the blocking member from blockingto unblocking position. Upon slight retraction and then extension of thebelt after buckled to another belt to form a belt assembly, the camplate is rotated toward the one limit position and the other abutment ofthe cam plate thereupon moves out of engagement with the pawl. The pawlis thenspring biased into engagement with like teeth of the ratchetmembers and prevents further extension of the belt. As the belt isretracted, the cam plate is moved to the one limit position and the oneplate abutment engages the pawl to hold it out of engagement with theratchet members. The one abutment of the ring gear passes the controllever, and the other abutment of the ring gear engages the control leverimmediately adjacent the fully retracted position of the belt to movethe control lever to the one position and move the blocking lever toblocking position.

SEATBELT RETRACTOR This invention relates to seatbelt retractors andmore particularly to seatbelt rctractors of the automatic locking type.

Seatbelt retractors of the automatic locking type generally include areel mounting a belt and being spring biased in a belt-retractingdirection. A ratchet and pawl arrangement permits movement of the reelin a belt-retracting direction at all times but blocks movement of thereel in an extending direction whenever the pawl engages the ratchet. Afirst sensor senses either the amount of belt wound on the reel or thenumber of rotations which the reel has made from a predeterminedretracted position, and holds the pawl out of engagement with theratchet until a certain length of belt has been extended or the reel hasrotated through a certain number of revolutions to extend such length ofbelt. Once this length of belt has been extended, the first sensor nolonger blocks movement of the pawl into engagement with the ratchet. Asecond rotatable sensor is frictionally driven by the reel and movesbetween predetermined limit positions at opposite ends of apredetermined arc of movement. The second sensor is in one limitposition at one end of its arc of movement when the belt is fullyretracted and cooperates with the first sensor in blocking engagement ofthe pawl with the ratchet.

Thus, the first and second sensors block engagement of the pawl with theratchet when the belt is fully retracted. When a predetermined length ofbelt is extended and the reel is rotated in an extending direction, thefirst sensor no longer blocks movement of the pawl into engagement withthe ratchet. The second sensor moves with the reel from the one limitposition to the other so that only the second sensor blocks the pawlafter the predetermined length of belt has been extended. Once the belthas been extended to whatever length is desired and buckled to anotherbelt to form the belt assembly, the reel is slightly wound in aretracting direction and then in an extending direction. The secondsensor moves with the reel from its other limit position to a positionintermediate the other limit position and the one limit position tothereby release the pawl for engagement with the ratchet and block anyfurther movement of the reel in an extending direction. Thus the belt islocked against further extension although retraction is permitted at alltimes.

The retractor of this invention is of the automatic locking type butincludes an improved first sensor for sensing the number of revolutionsof the reel an controlling the movement of the pawl into and out ofengagement with the ratchet.

In the preferred embodiment of the invention the first sensor includesblocking member swingable into and out of engagement with the pawl tothereby selectively block and unblock the pawl. The blocking member islinked to a swingable control member which is resiliently biased toeither of two positions. A reel-driven ring gear includes a pair ofspaced peripheral abutments of different radial extent. The ring gearabutment of greater radial extent engages the control member when thereel is immediately adjacent a fully belt-retracted position to move thecontrol member from one position to the other position and move theblocking member from unblocking to blocking position. When the reel isthereafter moved in a belt-extending direction through a predeterminednumber of revolutions. the other ring gear abutment of lesser radialextent engages the control member to move the control member from theother position to the one position and in turn move the blocking memberto unblocking position. After the other ring gear abutment engages andmoves the control member to the one position, it bypasses the controlmember and thereby permits full movement of the reel in a belt-extendingdirection. Thus, after a predetermined length of belt has been extended,only the friction-driven second sensor blocks the pawl. Thereafter thesecond sensor releases the pawl for engagement, with theratchet when thereel is first moved in a belt-retracting direction and then in abelt-extending direction. When the. reel is thereafter moved in abeltretracting direction, the other ring gear abutment bypasses thecontrol member and the one ring gear abutment engages the control memberwhen the belt is almost fully retracted to move the control member tothe other position and move the blocking member to blocking position.

The primary feature of this invention is to provide an improved sensorfor an automatic locking seatbelt retractor which senses the movement ofthe seatbelt reel in belt-extending and -retracting directions andincludes control means intermittently connected to the reel and movingblocking means into and out of engagement with a pawl to therebyselectively block and unblock movement of the pawl with respect to aseatbelt reel ratchet. Another feature of this invention is that thecontrol means includes a control member resiliently biased to either oftwo positions and moved between such positions by a reel-drivenrotatable ring gear having spaced abutments selectively and alternatelyengageable with the control member. A further feature of this inventionis that the spaced abutments of the ring gear are of different radialextent, the one abutment of greater extent engaging the control memberimmediately adjacent the fully retracted position of the belt to movethe control member to a first position and move the blocking member toblocking position, and the other abutment of lesser extent engaging thecontrol member after a predetermined length of belt has been extended tomove the control member to a second position and move the blockingmember to unblocking position, with the other abutment thereafterbypassing the control member during movement of the ring gear.

These and other features of the retractor of this invention will bereadily apparent from the following specification and drawings wherein:

FIG. I is a partial perspective view of a vehicle body having a seatmounted therein and a lap belt assembly for the seat, with the outboardlap belt being mounted on the body by a retractor according to thisinvention and being fully retracted;

FIG. 2 is an enlarged partially broken away view of a portion ofFlG. 1;

FIG. 3 is a partially broken away view taken generally along the planeindicated by line 3-3 of FIG. 2;

FIG. 4 is a partially broken away view taken generally along the planeindicated by line 4-4 of FIG. 2;

FIG. 5 is a view similar to FIG. 4 and showing the belt partiallyextended;

FIG. 6 is a view similar to FIG. 4 and showing a predetermined length ofbelt extended;

FIG. 7 is a view similar to FIG. 6 and showing a partial retraction ofthe belt after the belthas been extended beyond the predeterminedlength;

FIG. 8 is a view similar to FIG. 7 and showing continued retraction ofthe belt;

FIG. 9 is a sectional view of the retractor with a predetermined lengthof belt extended; and

FIG. I0 is a broken away perspective view of the retractor with the beltin fully retracted position.

Referring now particularly to FIG. I of the drawings, a vehicle bodydesignated generally 10 includes a floor pan 12 on which isconventionally mounted a conventional bucket-type vehicle seat 14 A lapbelt assembly is provided for the occupant of the seat and includes aninboard belt I6 conventionally anchored at one end 18 to the floor panl2 and provided with a conventional buckle 20 at its free end.

The outboard belt 22 is mounted on the floor pan I2 by a retractor 24 aaccording to this invention and includes a conventional D-ring at itsfree end which is cooperable with the buckle 20 when the belt 22 isextended to form a lap belt assembly for the occupant of seat 14. Sincethe retractor 24 is of the automatic locking type, no adjustment ofeither belt 16 or 22 is required for varying-size occupants.

As best shown in FIGS. 2, 3 and 10 of the drawings, the retractor 24includes a generally channel-shaped housing 26 having spaced end walls28 and 30 which are interconnected I by a base wall 32 provided withintegral depending apertured flanges 34. The flanges 34 areinterconnected by a pin 36. As shown in FIG. 2, a hook member 38 boltedto the floor pan 12 engages the pin 36 to thereby mount the housing 26on the floor pan 12. it will be noted that the flanges 34 are partiallycut away to fix the angular position of the retractor with respect tothe floor pan 12 and in turn fix the belt angle when the belt '22iscxtended frointhe retractor.

A shaft 40 extends through and is secured to like ttpertured ratchetplates 42 to provide n reel 44. Tire peripheries of the plates areprovided with a number of equally spaced axially aligned radialshoulders 46. The shoulders oteoch plate are in= terconnected by camsurfaces 48. The belt 22 is fully wound on reel 44 when it is fullyretracted and is unwound from the reel when it is extended, as will befurther described. As best shown in FIG. 9, the looped inner end of thebelt 22 receives the shaft 40 and a spring clamp 50 is fitted over thelooped end of the belt to thereby secure the belt to the reel.

The reel 44 is rotatably mounted on the housing 26 by journaling one endof the shaft 40 within an aperture 52, FIG. 2, in end wall 30 andjournaling the reduced diameter slotted other end 54 of the shaft withina hushed opening in the other end wall 28. A conventional clock spring46 has its outer spiral suitably anchored to the wall 28 and its innerspiral received within the slotted end 54 of the shaft 40 to therebycontinually bias the reel 44 in a clockwise direction as viewed in FIGS.3 through of the drawings or, in other words, continuously bias the reelin a belt-retracting direction. A conventional cover 58 secured to wall28 covers the clock spring.

From the fore oing description, it can be seen that when the D-ring onthe outer end ol the belt 22 is manually grasped by an occupant of thesent 14 and pulled, the reel 44 will be rotated in a counterclockwise orbelt-extending direction as viewed in FIGS. 3 through 10 against theaction of the spring 56.

As best shown in H6. 10, a flat pawl 60 extends between the walls 28 and30 and is rotatably received within hourglassshaped openings 62 in thewalls. The pawl 60 includes lateral extensions 64 which extend towardthe ratchet plates 42 and are engageable with any respective pair ofshoulders 46 thereof to block movement of the reel 44 in acounterclockwise or belt-extending direction As best shown in FIG. 10,the pawl 60 further includes a lateral extension 66 located outboard ofthe wall 30. A leaf spring 68 has the free offset end thereof engagingthe extension 66 to continually bias the pawl 60 clockwise and therebybias the extensions 64 into engagement with the peripheries of theratchet plates 42 and, of course, into engagement with the adjacent pairof shoulders 46 upon counterclockwise movement of the reel 44.

Referring now particularly to FIG. 10, a plastic plate 70 fits againstthe outer surface of the end wall 30 and is secured thereto in anysuitable manner. Integral lateral tabs 72 of this plate engage over oneend ofthe spring 68 to mount the spring thereon.

As previously mentioned, the retractor includes blocking means movableinto and out of engagement with the pawl to thereby block and unblockmovement ofthe pawl with respect to the ratchet plates. The blockingmeans includes a blocking member 78 pivoted at 80 to the plate 70. Achamfered foot 82 of member 78 is engageable with extension 66 oppositethe spring 68 when thc blocking member is in blocking position, as shownin FIGS. 4, 5 and 10, to thereby hold the extensions 64 out ofengagement with the ratchet plates 42. When the blocking member 78 is inunblocking position, as shown in FIGS. 6, 7 and 8, the foot 82 does notengage the extension 66 of the pawl 60. The extensions 64 then engagethe peripheries of the ratchet plates 42 under the action of spring 68and engage the adjacent pair of shoulders 46 of the plates uponcounterclockwise movement of the reel 44.

A control member 84 is pivoted at 86 to the plate and an overcenter typecoil torsion spring 88 extends between one end of the control member 84and the plate 70 to selectively and alternately bias the member 84clockwise and counterclockwise about the pivot 86. A rod link 90pivotally interconnccts the control member 84 and the blocking member78. When the control member is in its one position shown in FIGS. 4 and5, the blocking member is in blocking position and the spring 88 biasesthe control member counterclockwise about the pivot 86. No stop is, ofcourse, needed for the control member since the engagement of the foot82 of the blocking member with the extension 66 provides such a stop.

When the control member is in its other position shown in FIGS. 6 and 8,the blocking member is in unblocking position and the spring 88 biasesthe control member clockwise about the pivot 86. The engagement of thecontrol member with a lateral tab 92 of the plate '70 provides a step.

A spur gear 94 is formed integral with the end of the shaft 40 journnledin the end wall 30. The plate 70 includes an integrul circular wall orflange 96 of very slight height and an intcgrally toothed ring gear 98is journaled within this wall for rotation about an axis eccentric tothe axis of the shaft 40. The internal teeth of the ring gear mesh withthe teeth of the spur gear 94 so that upon rotation of the shaft 40, thering gear 98 is rotated about its own axis.

The external periphery of the ring gear includes a first abutment 100extending radially thereof and a second abutment 102 which also extendsradially but to a lesser extent than the abutment 100.

When the ring gear is rotated clockwise, the engagement of the abutment100 with the control member 84, as shown in FIGS. 4 and 10, moves thecontrol member counterclockwise of the pivot 86 to its one position tolocate the blocking member in blocking position. When the ring gear isrotated counterclockwise, the engagement ofthe abutment 102 with achamfered foot 104 of the control member 84 will swing the controlmember clockwise of the pivot 86 to its other position shown in FIG. 6to move the blocking member to unblocking position. The abutment 102 andthe chamfered foot 104 are arranged to bypass each other when thecontrol member84 is in its other position as shown in FIG. 6.

A cam plate 106 fits between the ratchet plate 42 and the end wall 30and includes a pair of abutments or shoulders 108 and 110, as shown inFIG. 3. The plate 106 also includes a an integral lateral tab 112 whichextends outwardly through an arcuate slot 114 of predetermined extent inthe end wall 30. A wavy-type spring washer 116 seats between the plate106 and the wall 30, as shown in FIG. 2, to continually bias the plate106 into frictional engagement with the ratchet plate 42. The engagementof the lateral tab 112 with either end wall 118 or 120 of the slot 114locates the plate 106 against movement with the reel, as will be furtherdescribed.

When the belt is in a fully retracted position as shown in FIGS. 2, 3, 4and 10, the abutment 100 of ring gear 98 engages the control member 83and the blocking member 78 is located in unblocking position. Theengagement of the chamfered foot 82 of the blocking member with theextension 66 under the action of spring 88 rotates the pawl 60 counterclockwise within the openings 62 to maintain the extensions 64 out ofengagement with the peripheries of the ratchet plates 42 against theaction of spring 68.

The cam plate 106 has its lateral tab 112 engaging the wall 118 of slot114 to locate shoulder 110, as shown in FIG. 3 in engagement with one ofthe extensions 64 to additionally hold the extensions 64 of pawl 60 outof engagement with the peripheries of the ratchet plates 42. Reel 44 isthus free to rotate in a counterclockwise or belt-extending direction.

When a seated occupant graphs of the D-ring and pulls the belt 22outwardly of the retractor 24, the reel 44 rotates counterclockwise, asviewed in FIGS. 3, 4, 5, 6 and 10 of the drawings against the action ofspring 56. Upon a few degrees of counterclockwise movement, the shouldermoves out of engagement with the one extension 64 of pawl 60 as the tab112 of the cam plate 106 moves away from the wall 118 and toward thewall 120. Upon further counterclockwise movement, tab 112 engages thewall as shown in FIG. 5 so that shoulder 108 now engages the extension74. During this movement of the cam plate, the ring gear 98 rotates in acounterclockwise direction and the blocking member remains in unblocking position as abutment I moves counterclockwise away from thefoot 104 of control member 84 and abutment I02 moves counterclockwisetoward the foot 104 of the control member.

When the predetermined length of belt has been extended abutment 102engages foot 104, as shown in FIG. 6, and swings the control member 84clockwise of the pivot 86 from its FIG. 5 position to its FIG. 6position in engagement with tab 92 as spring 88 goes over center. Link90 thereupon moves the blocking member to unblocking position. Howeverthe extensions 64 of pawl 60 remain out of engagement with theperipheries of the ratchet plates 42 since it will be remembered thatthe abutment 108 of plate 106 engages one extension 64. Thus, after apredetermined length of belt has been extended, only the cam plate 106blocks engagement of the extensions 64 of the pawl with the ratchetplates 42.

Normally, the occupant will further extend the belt 22 around himself toengage the D-ring of this belt with the buckle of belt 16 and form thelap belt assembly. During this further movement of belt 22, only ringgear 49 rotates and abutment 102 bypasses foot 104 and movescounterclockwise thereof. After belts l6 and 22 have been engaged, theoccupant releases the belt 22 and the spring 56 rotates reel 44 in aclockwise or belt-retracting direction until the belt assembly snuglyengages the occupant. As the reel rotates in a clockwise direction, thecam plate 106 moves with the reel from its FIG. 6 position to either itsFIG. 3 position or a position intermediate these positions. depending onthe arc of movement of the reel necessary to snugly engage the beltassembly with the occupant. Thus. either shoulder 100 of the cam plate106 will engage the pawl extension 64, as shown in FIG. 3, or the pawlextension 64 will be located between shoulders 108 and 110. If thelatter occurs, spring 68 moves the pawl extensions 64 into engagementwith the cam surfaces 46 of each ratchet plate. Thereafter the occupantslightly retracts the belt 22 to pull the belt assembly tight about himas the pawl extensions ratchet over the shoulders 46 of the ratchetplates counterclockwise thereof. Cam plate 106 either remains in itsposition shown in FIG. 3 or moves to this position.

The occupant then extends the belt 22 so that the pawl extensions 64engage the shoulders 46 of the ratchet plates clockwise thereof to lockthe belt 22 against further extension. During this movement, the camplate 106 moves slightly counterclockwise to its position shown in FIG.7 wherein tab 112 is located between walls 118 and 120.

When the occupant releases the buckle 20 from the D-ring, the spring 56rotates the reel 44 in a clockwise or belt-retracting direction. The camplate 106 moves with the reel 44 from its position shown in FIG. 7 toits position shown in FIG. 8 so that tab 112 engages the wall 118 ofslot 114 and shoulder 110 engages the one extension 64 of the pawl tomove the pawl out of engagement with the ratchet plates. The ring gear98 rotates in a clockwise direction and abutment I02 bypasses foot 104and moves clockwise thereof. Immediately before the belt 22 is fullyretracted. abutment I00 engages the foot 104 of the control member 84.as shown in FIG. 8, and immediately thereafter moves the control member84 from its FIG. 8 position to its FIG. 4 position to again move theblocking member 78 to blocking position in engagement with the pawlextension 66 and cooperate with the shoulder 110 in holding the pawlextension 64 out of engagement with the ratchet members 42.

A suitable flanged cover 122 is provided for the plate 70 and may besecured thereto by hot staking plurality ofintegral lateral tabs of theplate to the cover as shown in FIG. 10. The conventional cover 124, FIG.1, covers the housing 24 and includes a slot for passage of belt 22therethrough. The conventional enlarged sewn portion of the beltattaching the D-ring thereto engages the cover 124 adjacent the slottherein to fix the fully retracted position of belt 22.

Thus, this invention provides an improved seatbelt retractor.

Iclaim:

1. In a retractor having support means, reel means rotatably mounted onthe support means, belt means mounted on the reel means for extensionand retraction relative thereto upon rotation of the reel means inextending and retracting directions relative to the support means, meansbiasing the reel means in a retracting direction to retract the beltmeans and stop means, normally operative to hold the reel means againstmovement in an extending direction and to permit movement in aretracting direction by said biasing means, the combination comprising,a blocking member mounted on the support means for movement between ablocking position wherein the blocking member blocks the stop means andan unblocking position wherein the blocking member permits operation ofthe stop means, means releasably holding the blocking member selectivelyand alternately in blocking or unblocking position, moving meansoperable to move the blocking member between blocking and unblockingpositions, and reel-driven means intermittently operatively connected tothe moving means during movement of the reel means for actuating themoving means to move the blocking member to unblocking position uponmovement of the reel means in an extending direction and to move theblocking member to blocking position upon movement of the reel means ina retracting direction.

2. In a retractor having support means reel means, reel means rotatablymounted on the support means, belt means mounted on the reel means forextension and retraction relative thereto upon rotation of the reelmeans in extending and retracting directions relative to the supportmeans, means biasing the reel means in a retracting direction to retractthe belt means and stop means, normally operative to hold the reel meansagainst the movement in an extending direction and to permit movement ina retracting direction by said biasing means, the combinationcomprising, a blocking member mounted on the support means for movementbetween a blocking position wherein the blocking member blocks the stopmeans and an unblocking position wherein the blocking member permitsoperation of the stop means, a control member mounted on the supportmeans for movement between first and second positions relative thereto,means operably connecting the control member to the blocking member tomove the blocking member between blocking and unblocking positions uponmovement of the control member between first and second positions, andreel-driven means intermittently operatively connected to the controlmember during movement of the reel means for actuating the controlmember to move the blocking member to unblocking position upon movementof the control member to the first position and movement of the reelmeans in an extending direction, and to move the blocking member toblocking position upon movement of the control member to the secondposition and movement of the reel means in a retracting direction.

3. In a retractor having support means, reel means rotatably mounted onthe support means, belt means mounted on the reel means for extensionand retraction relative thereto upon rotation of the reel means inextending and retracting directions relative to the support means, meansbiasing the reel means in a retracting direction to retract the beltmeans and stop means, normally operative to hold the reel means againstmovement in an extending direction and to permit movement in aretracting direction by said biasing means, the combination comprising,a blocking member pivoted to the support means for swinging movementbetween a blocking position wherein the blocking member blocks the stopmeans and an unblocking position wherein the blocking member permitsoperation of the stop means, a control member pivoted to the supportmeans for swinging movement between first and second positions relativethereto, a link pivotally interconnecting the blocking member andcontrol member to move the blocking member between blocking andunblocking positions upon movement of the control member between firstand second positions, and a reel-driven annular member rotatably mountedon the support means and intermittently operatively connected to thecontrol member having spaced peripheral means during movement of thereel means for actuating the control member to move the blocking memberto unblocking position upon movement of the control member to the firstposition and movement of the reel means in an extending direction, andto move the blocking member to blocking posi tion upon movement of thecontrol member to the second position and movement of the reel means ina retracting direction.

4. In a retractor having support means, reel means rotatably mounted onthe support means, belt means mounted on the reel means for extensionand retraction relative thereto upon rotation of the reel means inextending and retracting directions relative to the support means, meansbiasing the reel means in a retracting direction to retract the beltmeans and stop means normally operative to hold the reel means againstmovement in an extending direction and to permit movement in aretracting direction by said biasing means, the combination comprising,first blocking means for the stop means moveable by the reel means to apredetermined blocking position with respect to the stop means uponrotation of the reel means in an extending direction through apredetermined arc, second blocking means for the stop means mounted onthe support means for movement between blocking and unblocking positionswith respect to the stop means, means locating the second blocking meansin blocking position during movement of the reel means through thepredetermined arc, cooperating means on the reel means and the secondblocking means intermittently connected upon movement of the reel meansthrough an are greater than the predetermined are for moving the secondblocking means to unblocking position, and means relocating the secondblocking means in blocking position during movement of the reel means ina retracting directionr 5, The combination recited in claim 3 whereinthe reeldriven annular member includes an internally toothed ring geardriven by a reel-driven gear and having a pair of peripherally spacedradially extending abutments selectively and alternately engageable withthe control member during movement of the reel means.

6. The combination recited in claim 3 wherein the reeldriven annularmember includes a ring gear driven by the reel means and having a pairof peripherally spaced radially extending abutments of different extent,the abutment of lesser radial extent engaging the control member to movethe blocking member to unblocking position and the abutment of greaterradial extent engaging the control member to move the blocking member toblocking position, and cooperating means on the control member andabutment of lesser radial extent permitting the abutment of lesserradial extent and control member to bypass each other after engagementthereof.

7. The combination recited in claim 3 including overcenter spring meansinterconnected between the control member and support means andselectively and alternately biasing the control member to either thefirst position or the second position thereof, and stop means engageableby the control member upon movement thereof to the first position tolocate the control member against the action of the overcenter springmeans, engagement of the blocking member with the pawl providing a stoplocating the control member in the second position thereof against theaction of the overcenter spring means.

Po-ww UNITED STATES PATENT OFFICE W69) CERTIFICATE OF CORRECTION PatentNo. 3,598,336 Dated August 10, 1971 Inventor(s) It is certified thaterror appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 1, line 47, "an" should read and Column 2, line 61, after "14"insert a period line 66, after "24" delete "a".

Column 3, line 22, "46" should read 56 Column 4, line 40, after"includes" delete "a".

line 51, "83" should read 84 line 64, "graphs" should read grasps line74, "74" should read 64 Column 5, line 21, "49" should read 98 line 31,"100" should read 110 line 35, after "cam surfaces" insert 48 of theratchet plates between a pair of successive shoulders line 67, "The"should read A V Column 6, line 7, delete the comma J line 31, delete thecomma (J. line 60, delete the comma Signed and sealed this 29th day ofFebruary 1972.

(SEAL) Attest EDWARD NLFLETCHER,JR. ROBERT GOI'TSCHALK Attesting OfficerCommissioner of Patents

1. In a retractor having support means, reel means rotatably mounted onthe support means, belt means mounted on the reel means for extensionand retraction relative thereto upon rotation of the reel means inextending and retracting directions relative to the support means, meansbiasing the reel means in a retracting direction to retract the beltmeans and stop means normally operative to hold the reel means againstmovement in an extending direction and to permit movement in aretracting direction by said biasing means, the combination comprising,a blocking member mounted on the support means for movement between ablocking position wherein the blocking member blocks the stop means andan unblocking position wherein the blocking member permits operation ofthe stop means, means releasably holding the blocking member selectivelyand alternately in blocking or unblocking position, moving meansoperable to move the blocking member between blocking and unblockingpositions, and reel-driven means intermittently operatively connected tothe moving means during movement of the reel means for actuating themoving means to move the blocking member to unblocking position uponmovement of the reel means in an extending direction and to move theblocking member to blocking position upon movement of the reel means ina retracting direction.
 2. In a retractor having support means, reelmeans rotatably mounted on the support means, belt means mounted on thereel means for extension and retraction relative thereto upon rotationof the reel means in extending and retracting directions relative to thesupport means, means biasing the reel means in a retracting direction toretract the belt means and stop means normally operative to hold thereel means against movement in an extending direction and to permitmovement in a retracting direction by said biasing means, thecombination comprising, a blocking member mounted on the support meansfor movement between a blocking position wherein the blocking memberblocks the stop means and an unblocking position wherein the blockingmember permits operation of the stop means, a control member mounted onthe support means for movement between first and second positionsrelative thereto, means operably connecting the control member to theblocking member to move the blocking member between blocking andunblocking positions upon movement of the control member between firstand second positions, and reel-driven means intermittently operativelyconnected to the control member during movement of the reel means foractuating the control member to move the blocking member to unblockingposition upon movement of the control member to the first position andmovement of the reel means in an extending direction, and to move theblocking member to blocking position upon movement of the control memberto the second position and movement of the reel means in a retractingdirection.
 3. In a retractor having support means, reel means rotatablymounted on the support means, belt means mounted on the reel means forextension and retraction relative thereto upon rotation of the reelmeans in extending and retracting directions relative to the supportmeans, means biasing the reel means in a retracting direction to retractthe belt means and stop means normally operative to hold the reel meansagainst movement in an extending direction and to permit movement in aretracting direction by said biasing means, the combination comprising,a blocking member pivoted to the support means for swinging movementbetween a blocking position wherein the blocking member blocks the stopmeans and an unblocking position whereIn the blocking member permitsoperation of the stop means, a control member pivoted to the supportmeans for swinging movement between first and second positions relativethereto, a link pivotally interconnecting the blocking member andcontrol member to move the blocking member between blocking andunblocking positions upon movement of the control member between firstand second positions, and a reel-driven annular member rotatably mountedon the support means and intermittently operatively connected to thecontrol member having spaced peripheral means during movement of thereel means for actuating the control member to move the blocking memberto unblocking position upon movement of the control member to the firstposition and movement of the reel means in an extending direction, andto move the blocking member to blocking position upon movement of thecontrol member to the second position and movement of the reel means ina retracting direction.
 4. In a retractor having support means, reelmeans rotatably mounted on the support means, belt means mounted on thereel means for extension and retraction relative thereto upon rotationof the reel means in extending and retracting directions relative to thesupport means, means biasing the reel means in a retracting direction toretract the belt means and stop means normally operative to hold thereel means against movement in an extending direction and to permitmovement in a retracting direction by said biasing means, thecombination comprising, first blocking means for the stop means moveableby the reel means to a predetermined blocking position with respect tothe stop means upon rotation of the reel means in an extending directionthrough a predetermined arc, second blocking means for the stop meansmounted on the support means for movement between blocking andunblocking positions with respect to the stop means, means locating thesecond blocking means in blocking position during movement of the reelmeans through the predetermined arc, cooperating means on the reel meansand the second blocking means intermittently connected upon movement ofthe reel means through an arc greater than the predetermined arc formoving the second blocking means to unblocking position, and meansrelocating the second blocking means in blocking position duringmovement of the reel means in a retracting direction.
 5. The combinationrecited in claim 3 wherein the reel-driven annular member includes aninternally toothed ring gear driven by a reel-driven gear and having apair of peripherally spaced radially extending abutments selectively andalternately engageable with the control member during movement of thereel means.
 6. The combination recited in claim 3 wherein thereel-driven annular member includes a ring gear driven by the reel meansand having a pair of peripherally spaced radially extending abutments ofdifferent extent, the abutment of lesser radial extent engaging thecontrol member to move the blocking member to unblocking position andthe abutment of greater radial extent engaging the control member tomove the blocking member to blocking position, and cooperating means onthe control member and abutment of lesser radial extent permitting theabutment of lesser radial extent and control member to bypass each otherafter engagement thereof.
 7. The combination recited in claim 3including overcenter spring means interconnected between the controlmember and support means and selectively and alternately biasing thecontrol member to either the first position or the second positionthereof, and stop means engageable by the control member upon movementthereof to the first position to locate the control member against theaction of the overcenter spring means, engagement of the blocking memberwith the pawl providing a stop locating the control member in the secondposition thereof against the action of the overcenter spring means.